Question

the graph below shows a substance changing state as the temperature drops. study the graph to answer the questions below.

1. at which point in the graph is the substance a gas?
2. at which point is it a liquid?
3. at which point is it a solid?
4. where is condensation happening?
5. at what temperature does this substance begin to condense?
6. where is freezing happening?
7. at what temperature does this substance begin to freeze?

Explanation:

1. Gas phase: In the cooling curve, the substance is in the gas phase before it starts to condense. In the graph, region A shows the temperature decreasing while the substance is still a gas.
2. Liquid phase: After condensation (region B), the substance is in the liquid phase (region C) as it cools further before freezing.
3. Solid phase: After freezing (region D), the substance is in the solid phase (region E).
4. Condensation: Condensation occurs when a gas turns into a liquid. In the graph, this is shown in region B where the temperature remains constant (latent heat of condensation is released).
5. Condensation temperature: The horizontal line in region B indicates the condensation temperature. From the y - axis, it is 120°C.
6. Freezing: Freezing occurs when a liquid turns into a solid. In the graph, this is shown in region D where the temperature remains constant (latent heat of freezing is released).
7. Freezing temperature: The horizontal line in region D indicates the freezing temperature. From the y - axis, it is 20°C.

Answer:

1. A
2. C
3. E
4. B
5. 120°C
6. D
7. 20°C